The present application is related to the control systems for model railroad systems, and in particular, to a method and apparatus for detecting the presence and direction of any movement of an electrically driven model train along a track system to activate relays, accessories, or directional indicator signals.
Model railroad systems are becoming increasingly popular among hobby and train enthusiasts. Typically, in a model railroad system, sections of track are laid out and interconnected with various junctions and switches to provide one or more track pathways for an electrically driven model train to travel along. The electrically driven model train generally receives a supply of electrical power through the conductive portions of the track sections over which it travels. The direction of movement of the model train is regulated by the electrical polarity of the two rails in each track section, and correspondingly, the direction of an electrical current flow from the conductive rails through the electrical motor in the model train. For a first polarity, the model train will be driven in a first direction. By switching the polarity of an electrical potential supplied to the two rails with a reversing switch or relay, such as a double pole double throw switch, the direction of travel of the model train is correspondingly reversed.
To sustain movement of a model train around a track layout, sequential segments of track must be supplied with driving electrical power of matching polarity, and down-track junctions must be electrically switched to continue the motion or route the train in the correct direction. Furthermore, it is necessary to provide a means to identify the current track segment on which the model train is presently occupied and the direction of any movement of the train. On basic model train layouts, much of this is done by visual observation of the model train position and direction of motion, allowing an operator to ensure that sequential segments of track onto which the model train will move are provided with the correct polarity. However, on large scale model train layouts, the position and direction of movement of the model train may not be visible to an operator at all times, and multiple model trains may be moving about the tracks simultaneously.
Accordingly, there is a need to provide an apparatus which is capable of providing an operator with a signal indicating the presence of a train on a track segment, and the direction of travel of the train across that track segment. It would further be advantageous to provide an apparatus which is capable of utilizing the detected presence and direction of travel of a model train to selectively activate one or more down-track junctions or track segments to maintain automatic movement of the model train in the desired direction.